To the latest on edward snowden, hiding out in hong hong, making explosive new charges as the head of the nsa defends the program to congress saying it prevented dozens of terrorists attacks. Snowden carefully choreographing the rollout of the disclosures and one week after the first act of the real life drama he says he's ready for act two. Snowden emerged overnight to say he's still in hong kong, telling the south sigh that morning post it is there that he wants to make his last stand, to reveal more evidence of what he called the criminality of the u.S. And its operation against u.S. Citizens and targets worldwide. We want hong hong people to know than hong kong and china are also in a way victims of this surveillance program. Reporter: Officials say snowden may be holding nor secrets. His last post was in the nsa facility in hawaii, that is a hub for american spying and computer hacking on targets in china and north korea and hong kong. We don't know who the targets are, if that ever comes out, then there will be some serious damage to national security. Reporter: In his testimony before congress on wednesday, general keith alexander, head of the nsa, said snowden has already hurt the u.S. Great harm's already been done by opening this up. Reporter: Snowden grew up in the shadows was nsa headquarters in suburban maryland and overnight a new aspect of his complicated personality came through as seen in postings on a graphic arts website. A young rebel who dropped out of high school as a sophomore and tried modeling. The public education system turned its wretched, spiked back on me, he wrote on a blog. Yet even without formal education snowden was able to rise rapidly in the intelligence community because of technical skills and officials at the nsa say they're still at a loss to find out how he got his hands on so many top secrete. He had four laptop computers jammed with u.S. Secret documents. Other top stories from josh. Boy, already a rough day in the

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